Flange couplings are available to join two tubular conduits to one another in a fluid tight manner allowing passage of fluid from one conduit to another without leaks occurring between the conduits or where the two conduits are joined to each other. The conduits can have any suitable form, such as for example, tubular pipes, valves, taps, or other fitting used in conveying fluids from one location to another location in which one or more parts of one conduit is joined to one part of a second conduit, including conduits requiring two or more connections to other conduits.
Initially, the flange of the coupling connector, or other fitting, was made from metal, particularly unprotected metal, such as for example, steel having exposed bare surfaces, that were susceptible to corrosion. In many instances, the conduit to which the connector or fitting was attached was made from copper or a copper alloy. When a pair of flange couplings having bare exposed metal surfaces were located in opposed face-to-face relationship to each other, say at the end of one pipe to join the pipe to a fitting, such as for example, the inlet or outlet of a valve, electrolysis action often occurred between the two dissimilar metals of copper and steel, particularly in environmental conditions conducive to such action, such as for example in moist or wet conditions after encountered underground. The electrolysis action often resulted in electrolysis corrosion of the steel coupling, copper tube, or both leading to a failure of the junction between them thereby resulting in leakage of the contents of the copper pipe at or close to the junction.
One attempt to address the electrolysis action was to provide a gasket or similar between the copper tube and one of the components of the steel flange coupling. Typically, the gasket acted to isolate or insulate the steel flange coupling from the copper pipe or similar, to prevent the steel flange from coming into contact with the copper tube in an attempt to prevent corrosion. However, over time, the gasket deteriorated or degraded leading to failure of the integrity of the gasket allowing direct contact between the exposed bare surface of the steel flange and the surface of the copper pipe which in turn resulted in electrolysis taking place due to the two dissimilar metals being in contact with each other in a wet or moist environment leading to corrosion. Thus, there is a need for an improvement in joining a copper pipe to another fitting including a second copper pipe which reduces or eliminates the chance of electrolytic corrosion occurring between the pipe and the connector where the metals of the pipe and connector are dissimilar.
Another disadvantage of having to use a gasket or similar to separate the flange coupling from the pipe, is the added cost and effort during manufacture and packaging to provide the correct size gasket for the size of the pipe, or pipe fitting, sleeve or the like, and to place the correct gasket with the steel flange in the package containing the flange connector as well as having to install the gasket over the pipe during assembly of the installation which requires extra care and attention as well as additional time to align all of the components needed to form the junction.
Accordingly, it is an aim of the invention to provide an improved connector for joining a conduit to either another conduit or to a fitting in which the connector includes one or more flange couplings having improved corrosion resistance.
Accordingly, it is an aim to provide a flange coupling which has improved longevity and is more durable by having increased corrosion resistance to the adverse effects of electrolytic or galvanic corrosion.
Accordingly, it is an aim to provide a flange coupling or connector having a protective layer or coating which renders the flange coupling more resistant to electrolytic corrosion by changing the electrolytic or galvanic characteristics of the flange coupling.
Accordingly, it is an aim of the present invention to more closely match the electrolytic characteristics of the connector to the conduit to reduce or eliminate the incidence of electrolytic corrosion.
Accordingly, it is an aim to provide a flange coupling having a protective layer in which the protective layer is matched to the material of the items being joined to each other so as to have the same or similar electrolytic or galvanic characteristics to the items being joined by the connector to reduce the occurrence of electrolytic corrosion.
It is to be noted that not all embodiments of the invention satisfy all aims or objective. Some embodiments will satisfy one aim, whilst other embodiments will satisfy other aims. Some embodiments will satisfy two or more aims of the invention.